Beams, joists and frames for construction work, for example in aeronautics, civil engineering or architecture, are designed to withstand bending forces acting perpendicular to the direction of extension of the respective beams. Conventional beams may be implemented as an integral part with flanges at the edges and a web spanning between the flanges. Alternatively, instead of a web, cutter milled struts may be implemented between parallel running longitudinal support bars, thus leading to decreased weight of the beam due to less material being used to form the beam.
In order to save weight on board of aircraft, there have been several attempts to optimize the design of structural aircraft components. For example, document WO 2014/111707 A1 discloses a method for designing an object that includes analysing a digital model corresponding to the object for portions that have been determined to, during use of the object, experience relatively high stresses. Those high stress regions are used to determine which portions of the object are to be produced using an Additive Manufacturing (AM) process, and which portions of the object are to be produced using a different suitable process, for example a machining process. Document DE 10 2010 064 100 A1 discloses a partition wall for separating cabin areas of an aircraft with a sandwich-like surface structure.
Structural topology optimization methods for designing structural objects according to predefined design criteria have for example been disclosed in the document WO 2007/076357 A2.
EP 0 191 245 A1 discloses a double end stud with a nut and externally threaded portions integrally formed on both axial ends of the nut. The threaded portions are threaded in opposite directions. In use, the double end stud is placed between the opposing surfaces of two structural members which are to be connected together. As the nut is rotated, the threaded portions are screwed into female screw members provided on the structural member, so that the structural members are pulled and connected together.
DE 204 52 59 A1 discloses a screwing connector with coaxial threads that has a distance sleeve accommodating driving tool sliding on a central driving portion thereof. DE 821 883 B discloses a double ended screw having a left-handed screw thread on one end and a right-handed screw thread on the other.
There is, however, a need for connectors capable of securing elongated structural members along their line extension which connectors allow for connection of the structural members with only minimal relative movement of the structural members with respect to each other being necessary.